This will be the ULA’s 6th launch of 2017, 121st launch overall, 73rd launch of the Atlas V, and the 5th launch of Atlas in its 541 configuration.

The United Launch Alliance (ULA) Atlas V-500 Series rocket is a two-stage rocket that depending on the size of the fairing used stands between 59.7 m (196 ft.) and 65.5 m (215 ft.) with a diameter of 12.5ft (3.81m) and consists of an Atlas Common Core Booster with a Russian RD-180 engine and first stage with a United States RL-10 Centaur upper stage built by AeroJet-Rocketdyne. The vehicle is available in 6 different configurations which are built specifically for each individual mission. Its launch sites are Cape Canaveral Air Force Station (CCAFS), Launch Complex-41 (LC-41) or Vandenberg Air Force Base, Launch Complex-3 (LC-3).

Main Payload Fairing (PLF): The Main Payload Fairing for the Atlas-V-500 series is a two-shell fairing that can come in three configurations. All 5 m (17.8 ft.) in diameter, there’s a 68 ft. (20.7 m) “short”, a 77 ft. (23.5 m) “medium” and an 87 ft. (26.5 m) “long” option for the fairing based on the payload. The fairings are used to protect the spacecraft & Centaur during its ascent through atmospheric turbulence and into space. Once the rocket has reached a safe altitude the fairings are pyrotechnically jettisoned via a debris-free actuating system.

Centaur Upper Stage: The Centaur Upper stage is 10 ft. (3.1 m) in diameter and 41.6 ft. (12.7 m) in length. It consists of a single Cryogenic RL-10C (RL-10C) Aerojet Rocketdyne Engine that provides 99.2 kN (22,300 lb.) of thrust and utilizes liquid hydrogen (LH2) for propellant and liquid oxygen (LOX) as an oxidizer with a burn time of up to 740 seconds to include multiple engine firings. There are also four 27-N (Newton) thrusters and eight 40-N (Newton) thrusters used for attitude control. Both utilize hydrazine as propellant. The Centaur Forward Adapter (CFA) provides structural mountings for vehicle electronics within the spacecraft.

Solid Rocket Booster’s (SRB’s): Have a diameter of 62.2 in. (158 cm) with a length of 65.6 ft. (20 m). The total number of SRB’s utilized is dependent on the individual mission and vary from none at all to 5. Each have a burn time of about 88.3 seconds.

Common Core Booster (CCB) (First-Stage): The American Atlas V Common Booster Core is 106.5 ft. (32.46 m) in length by 12.5 ft. (3.8 m) in diameter and is powered by a single two-chamber Russian RD-180 engine manufactured by NPO Energomash, that utilizes Rocket Propellant-1 (RP-1 or highly purified kerosene) as propellant and Liquid Oxygen (LOX) as the oxidizer. It provides 3,827 kN (860,300 lb.) of thrust at sea level and can burn for 311 seconds. The RD-180 engine is modeled after the 4-chanber RD-170 engines used by the Zenit rocket family.